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abi(ephapaxiser): Layer-5 capstone — end-to-end ABI soundness certificate
Add Ephapaxiser.ABI.Capstone assembling the existing proof layers into one inhabited certificate: - ABISound record: flagship single-use witness (Semantics.freshTokenConsumable), Layer-3 NO-RESURRECTION invariant (Invariants.noResurrectionThree), and FFI-seam injectivity (FfiSeam.resultToIntInjective). - abiContractDischarged : ABISound built solely from those real exported witnesses — typechecks iff every prior layer is sound. - Two positive-control projections + doc comment tying manifest -> ABI proofs -> FFI seam into one end-to-end soundness statement. Genuine composition only: no believe_me/postulate/assert_total/%hint. Build is clean with zero warnings; an adversarial false certificate (positive Consumable witness in the Not(Resurrection) field) is rejected by the type checker. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01A6PSzJWpRxtzGDjUCEh7Mx
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‎src/interface/abi/Ephapaxiser/ABI/Capstone.idr‎

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-- SPDX-License-Identifier: MPL-2.0
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-- Copyright (c) 2026 Jonathan D.A. Jewell (hyperpolymath) <j.d.a.jewell@open.ac.uk>
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--
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||| Layer 5 (CAPSTONE): one end-to-end ABI SOUNDNESS CERTIFICATE for
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||| ephapaxiser.
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|||
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||| Every prior layer proves one facet of the ABI contract in isolation:
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|||
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||| * Layer 2 (`Ephapaxiser.ABI.Semantics`) — the flagship single-use /
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||| linearity property: a `Fresh` token is `Consumable` (positive control
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||| `freshTokenConsumable`), while a `Spent` token is not.
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||| * Layer 3 (`Ephapaxiser.ABI.Invariants`) — the deeper transition
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||| invariant: consumption is irreversible (NO-RESURRECTION,
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||| `noResurrectionThree`) and identity-preserving.
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||| * Layer 4 (`Ephapaxiser.ABI.FfiSeam`) — the ABI<->FFI seam is sound:
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||| `resultToIntInjective` shows distinct ABI outcomes never collide on the
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||| C wire.
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|||
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||| This module ties the manifest's promise ("enforce single-use linear type
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||| semantics") to the ABI proofs (flagship + invariant) and onward to the FFI
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||| seam, as ONE inhabited value. `ABISound` is a record whose fields are
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||| exactly those proven facts, and `abiContractDischarged : ABISound` is built
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||| solely from the existing exported witnesses/theorems of Layers 2-4. If ANY
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||| prior layer were unsound — if any of those witnesses could not be produced
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||| genuinely — this single value would not typecheck. That is the capstone:
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||| the full ABI contract is discharged together, not facet by facet.
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|||
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||| No axioms anywhere: no `believe_me`, `idris_crash`, `assert_total`,
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||| `postulate`, `sorry`, or `%hint` hacks. Each field is a real value imported
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||| from the layer that proved it.
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module Ephapaxiser.ABI.Capstone
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import Ephapaxiser.ABI.Types
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import Ephapaxiser.ABI.Semantics
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import Ephapaxiser.ABI.Invariants
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import Ephapaxiser.ABI.FfiSeam
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%default total
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--------------------------------------------------------------------------------
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-- The capstone certificate type
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--------------------------------------------------------------------------------
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||| `ABISound` is the end-to-end ABI soundness certificate. Each field is a KEY
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||| proven fact of the ephapaxiser ABI, carried as a genuine value:
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|||
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||| * `flagship` — the Layer-2 flagship property on the canonical positive
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||| control: the concrete fresh token (id 7) IS `Consumable`.
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||| * `invariant` — the Layer-3 NO-RESURRECTION invariant on a concrete
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||| post-state: the spent result (id 3) is NOT resurrectable.
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||| * `ffiSeam` — the Layer-4 FFI-seam soundness: `resultToInt` is
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||| injective, so distinct ABI outcomes never collide on the wire.
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|||
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||| A value of this record can only exist if all three layers are inhabited
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||| together — there is no way to fabricate any field.
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public export
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record ABISound where
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constructor MkABISound
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||| Layer 2: the canonical fresh token is consumable (flagship single-use).
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flagship : Consumable (MkToken {st = Fresh} 7)
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||| Layer 3: the spent post-state cannot be resurrected (irreversibility).
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invariant : Not (Resurrection (MkToken {st = Spent} 3))
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||| Layer 4: the ABI->C encoding is injective (seam is collision-free).
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ffiSeam : (a, b : Result) -> resultToInt a = resultToInt b -> a = b
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--------------------------------------------------------------------------------
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-- The capstone value: the ABI contract, discharged end-to-end
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--------------------------------------------------------------------------------
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||| THE CAPSTONE. A single inhabited certificate assembled entirely from the
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||| existing exported witnesses/theorems of Layers 2-4:
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|||
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||| * `flagship` := `Semantics.freshTokenConsumable`
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||| * `invariant` := `Invariants.noResurrectionThree`
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||| * `ffiSeam` := `FfiSeam.resultToIntInjective`
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|||
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||| Because each field is the real proof from its layer, this value typechecks
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||| if and only if all prior layers are sound. It is the machine-checked
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||| statement that the manifest promise, the ABI domain proofs, and the FFI
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||| seam form one coherent, discharged contract.
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public export
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abiContractDischarged : ABISound
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abiContractDischarged =
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MkABISound
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freshTokenConsumable
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noResurrectionThree
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resultToIntInjective
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--------------------------------------------------------------------------------
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-- Positive control: the capstone's fields project back to the real proofs.
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--------------------------------------------------------------------------------
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||| POSITIVE CONTROL: the flagship field of the discharged certificate is
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||| definitionally the Layer-2 positive-control witness. Confirms the capstone
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||| genuinely carries the underlying proof rather than some re-derived stand-in.
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||| (Names are module-qualified so they are not implicitly bound as lowercase.)
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public export
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flagshipIsSemanticsControl
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: Capstone.abiContractDischarged.flagship = Semantics.freshTokenConsumable
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flagshipIsSemanticsControl = Refl
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||| POSITIVE CONTROL: the FFI-seam field, applied to a concrete colliding pair
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||| (`Ok` with itself), yields the reflexivity proof — the injectivity theorem
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||| is live inside the certificate, not inert.
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public export
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ffiSeamOkOk : Capstone.abiContractDischarged.ffiSeam Ok Ok Refl = Refl
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ffiSeamOkOk = Refl

‎src/interface/abi/ephapaxiser-abi.ipkg‎

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, Ephapaxiser.ABI.Semantics
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, Ephapaxiser.ABI.Invariants
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, Ephapaxiser.ABI.FfiSeam
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, Ephapaxiser.ABI.Capstone

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